Phylogeny (2024)

Phylogeny

Evolutionary history of a species or group of species

Systematics

The discipline that focuses on determining the relationships between taxa

taxonomy

The science of classifying and naming organisms, organizing them into hierarchical categories based on shared characteristics.

Bionomial nomenclature

A formal system for naming species, using two terms: the genus name and the species identifier.

Hierachial ranks of biological classification

Domain, kingdom, phylum, class, order, family, genus, species- created by Carolus Linnaeus

Divergent evolution

Two or more species diverge from a common ancestor, decend from the same ancestor but evolve separately

Convergent evolution

Two or more distinct species share traits not due to a common ancestor

Phylogenetic tree

A diagram that represents evolutionary relationships among various biological species based on their genetic or physical characteristics. — Hypothesis about evolutionary relationships

Sister taxa

Groups of organisms that share an immediate common ancestor and are each other's closest relatives.

3 Main keys of phylogenetic trees

Shows hypothezised descent, cannot infer ages of taxa or branches, does not assume taxon evolved from taxa next to it

Systematics

the broad discipline focused on determining the relatedness of taxa and organizing them

The discipline focused on naming and classifying organisms— a subdiscipline of systematics

Taxonomy

Phylogenetics

the discipline focused on learning the evolutionary history of an organism

What term would you use to describe the relationship between a coyote and a gray wolf

sister taxa

Basal Taxa

term used to describe organism that diverged from the rest of us early on

In a phylogenetic tree what does the numbers 1 and 2 refer to?

Branch points

Morphology and molecular data

Helps us guide systematics but molecular data is the most precise for determining evolutionary relationships.

Homology

a term used to describe how similar the structures, DNA or the development of two species are due to shared ancestry indicating evolutionary relationships

Analogy

The comparison between two things that are different but in some aspect are in common ; it often refers to structures that serve similar functions in different species but do not share a common ancestor.

Homology Vs. Analogy

What features are due to shared ancestry vs. what is due to convergent evolution

Molecular Homologies

Compares the similarity of comparable Dna segments of diff lengths — it takes in the deletions and insertions into account

Cladistics

a common approach of systematics to create phylogenetic trees

Clades

A group of organisms that includes an ancestor and all its descendants, representing a single branch on the tree of life.

Monophyletic

Ancestors species and all its descendants

Paraphyletic

Ancestor species and some but not all its descendants

Polyphyletic

Distantly related species but does not include their most recent common ancestor